The United States postal system as well as many foreign postal systems cancel postage applied to envelopes, post cards and various other stationery or parcel post objects, by applying a cancellation seal to the postage stamp affixed to the envelope. The cancellation seal usually is applied by a hand stamp or by machine stamp cancelling devices. To be thus cancelled, it is a requirement by law that the postage stamp being cancelled, be affixed to the exterior of an envelope, post card, etc. and that the cancellation seal bearing a bull's eye portion that contains both the date and the name of the post office doing the cancellation, be impressed upon the stamp being cancelled.
In cases where a new series of stamps is being issued, because of the demand by stamp collectors, the post office on the first day of issue of the new series of stamps will apply a special seal containing a First Day of Issue notice in the cancellation seal. This special First Day of Issue cancellation seal includes not only a bull's eye portion having the date and name of the post office thereon together with a killer bar cancellation segment, but also includes the First Day of Issue notice. The killer bar cancellation segment of the seal normally produces a quantity of parallel wavy lines that extend to and over a stamp being cancelled.
U.S. Pat. No. 4,641,578 issued Feb. 10, 1987 for a "Method and Device for Authentication of First Day of Issue Stamps" describes and claims a method and suitable envelope for the First Day of Issue authentication of sheets or panels (sometimes referred to as panes) of postage stamps having a selvage edge on the sheet of the stamps to which the First Day of Issue notice and cancellation seal is applied.